Lipids of lower plants, in particular of mosses, are studied especially in regard to their content of arachidonic and eicosapentaenoic acids. These acids are essential in higher animal life and, in reference to this, their metabolism in the lower plants will be studied under various environmental conditions. The biosynthesis of anacardic acids (long-chain-alkyl salicylic acids) in ginkgo and their interaction with microorganisms will be studied.